1. Field of the Invention
The present invention relates to a method and apparatus for delivering grease or some other lubricant to various locations on a vehicle. More particularly, the present invention relates to a method and apparatus used to conveniently ensure than an automatic lubrication system is functioning properly.
2. State of the Art
In order to function properly and to reduce premature wear, most motor vehicles require that joints in the chassis, steering mechanisms and other structures be lubricated periodically. On an truck, such lubrication is typically done every 8,000 to 10,000 miles when the oil is changed to ensure that premature wear does not develop.
With most large trucks, however, simply applying lubrication with every oil change is not sufficient. A large tractor-trailer truck or a bus may cover the 3-5,000 mile range in a matter of a week, and such vehicles are typically configured so that a much greater distance can be traveled between regular oil changes. Additionally, the significant weight of the truck or bus leads quickly to premature wear if the components are not frequently lubricated, and the significant cost of such vehicles necessitates that they be properly maintained.
To further complicate the lubrication process, a truck may have dozens or even a hundred different lubrication-receiving points which need periodic applications of grease, etc. A common number of lubrication-receiving points for many trucks is approximately thirty two, and the lubrication-receiving points are disposed at various locations around the truck. If each of these points were to be hand lubricated as is commonly done with automobiles, considerable time would be lost.
To overcome these concerns, automatic lubrication systems were developed. One common system utilizes a grease pump which is connected by a plurality of main conduits to a plurality of manifolds. Once in the manifolds, the grease is channeled down one of several secondary conduits in the form of runner lines, and is ultimately ejected from a lubrication fitting onto the surface which needs lubrication. FIG. 1 shows a plan view of the tractor of a tractor-trailer truck and the various points which may be lubricated by such an automatic lubrication system, generally indicated at 10.
When the user desires to lubricate the various lubrication points 14, the user activates a pump 18. The pump moves grease or some other lubricant through one or more conduits 22, which feed one or more manifolds 26. The runner lines 30 extend from each manifold 26 and each terminates at a lubrication point 14. Thus, the user is able to apply lubricant to each lubrication point from a single location.
One problem with such a system is that it is difficult for the user to tell if the system is working properly. If the conduit 22 has broken, the grease will flow out of the conduit and will not be applied to the various lubrication-receiving points 14. If such a situation is not caught quickly, considerable damage can be done to the vehicle.
More likely than not, however, a failure is in one of the runner lines 30 which extend from the manifold to a lubrication-receiving point 14. While the overall damage caused by such a failure is not as great as a failure of a main conduit 22, a failure in a runner line 30 is more likely to go for an extended period of time without being noticed. During this time, considerable damage can be done to the surface which should have been lubricated.
To prevent such an occurrence from happening, the driver of the truck or bus would occasionally have to crawl under the truck or bus and examine the autolubrication system to make such each part was working properly. Such an inspection, however, can take a considerable amount of time and is often inconvenient--especially in foul weather.
Thus, there is a need for a method and an apparatus which can be used to check such an autolubrication system to ensure that it is working properly and that each lubrication point is receiving the lubricant. Such a method and apparatus should enable the user to check each main conduit and each runner line to ensure that lubrication is being dispensed as desired. Such a method and apparatus should also enable the activation of the autolubrication system from a substantially remote location, i.e. when the user is adjacent any one of the lubrication points.